Following the release of highly positive across-the-board data from its phase 1/2a trial for its OPT-302 “trap” therapy in wet AMD, Opthea (Melbourne, Australia) said it intends to raise $45 million (AUD) in an equity offering to move OPT-302 into 3 additional studies. The studies will encompass a 350-patient phase 2b trial for treatment-naïve wet AMD patients, a smaller phase 2a trial for previously treated wet AMD patients, and a 90-patient phase 2a trial for patients with DME. The studies will employ a “pan-VEGF” approach to evaluate the efficacy of OPT-302, which combats VEGF C and D, in combination with Lucentis (ranibizumab; Genentech), which is proven effective against VEGF A.
The 51-patient phase 1/2a study was deemed “very encouraging” by lead investigator Pravin U. Dugel, MD, of Retinal Consultants of Arizona, who noted in a conference call that the 2 mg dose of OPT-302 (both in combination with Lucentis and as monotherapy) produced significant vision gains, plus reductions in both retinal thickness and subretinal fluid, with an excellent safety profile at 12 weeks. Positive results were consistent across all patient categories, including difficult-to-treat individuals who had previously had an average of 17 anti-VEGF injections. However, Dr. Dugel cautioned that the trial was early stage and that larger studies are needed to confirm and expand on the phase 1/2a findings.
“As clinicians, we recognize that we are reaching a ceiling for anti-VEGF monotherapy and that 33% of patients don’t achieve significant vision gains from these drugs,” said Dr. Dugel. “The time is ripe for a combination treatment that benefits a larger percentage of our patients.”
Opthea CEO Megan Baldwin, PhD, said the decision to begin a trial in DME later this year was based on the significant reduction of subretinal fluid achieved in the phase 1/2a study.
“We know that reducing fluid is a key to combating DME, which presents an opportunity for OPT-302 for that indication,” she said.
One of the key numbers to come out of the phase1/2a trial was that in 18 treatment-naïve patients who received the OPT-302/Lucentis combination monthly for 12 weeks (3 months), the mean change from baseline was +10.8 letters. That far exceeded the mean change of +5.9 letters achieved with Lucentis monotherapy at 3 months in the pivotal phase 3 MARINA study.